Despite its name, morning sickness can appear at all times of the day and especially when the blood sugar level is low; this typically happens in the morning as a normal consequence of not having eaten during the night. It is therefore very common to experience this "morning" sickness - in the morning. There are large individual variations - also on a day-to-day basis. Some women do not experience this nausea at all and some women feel sick most of the day. Morning sickness is usually only present during the first 3 months of pregnancy.
It is believed that the nausea is caused by hormonal factors but is enhanced by the way the body metabolizes carbohydrates (sugars and starch).
Sustained and severe cases of vomiting can lead to weight loss and loss of important minerals (electrolytes).
Severe cases of nausea and vomiting can possibly be caused by intestinal infection with the bacterium Helicobacter pylori which is also responsible for many cases of gastric ulcers. It can stay in the intestine without necessarily causing symptoms.
